Leonardo da Vinci designed an organ gun with multiple parallel barrels.
An organ gun is a volley weapon made from several small guns arranged together. Leonardo’s version placed many barrels in a row or grouped formation so that they could fire repeatedly or in rapid succession. The name comes from the visual resemblance between the barrels and the pipes of a musical organ.
The design aimed to increase the rate of fire compared with a single muzzle-loading gun. A crew could prepare one group of barrels while another fired, at least in principle. Like many of Leonardo’s military drawings, the weapon was a proposal rather than a documented battlefield success.
An organ gun is not the same as a machine gun. It does not use a continuous automatic loading and firing system. It is also distinct from Leonardo’s giant crossbow and armored vehicle, which were separate designs addressing different military problems.